Hanshi of Muso Jikiden Eishin-Ryu Iaido, Chagao Maruyama demonstrates Gedan no Kamae, a powerful defensive position which employs the Mine (back spine) of the Katana to ward off an attack from above.  It is deceptive and appears weak to an opponent, especially when performed from the TateHiza, half-kneeling position, but the skilled Iaidoka can break the sword of the opponent in this defense.